Fox News host Greta Van Susteren didn't accept Donald Trump's explanation that he was talking about Carly Fiorina's persona when he told a Rolling Stone writer that people wouldn't want to vote for someone with such a face.

"I have got to tell you, I do take issue with your personal comment at another candidate like that," Van Susteren said. "I know you have made personal comments about others like [former Texas] Gov. [Rick] Perry and others. … Do you want to take it back about Carly Fiorina?"

Trump insisted he wasn't talking about Fiorina's looks, and said he was speaking in jest when he said, "Look at that face! Would anyone vote for that? Can you imagine that, the face of our next president? She's a woman, and I'm not s'posedta say bad things, but really, folks, come on. Are we serious?"

"I don't think you are a first time offender making a personal crack at a woman, that's the first thing," Van Susteren replied, a reference to Trump's comments about Van Susteren's fellow Fox host Megyn Kelly. "Second thing is that … the remark was about her face and not about her persona."

"My objection to you is that I just thought it was low rent to take a swipe at her looks," Van Susteren said.

She also defended Ben Carson, who attacked Trump's faith on Wednesday. Trump fired back that Carson wasn't known as a person of faith himself until recently, and added that the renowned pediatric neurosurgeon was an "OK doctor."

"I will tell you he is not merely an OK doctor," Van Susteren said. "I will take issue with that. He is a darn good doctor and saved a lot of lives. Why are you saying that about him?"

"I'm not sure everybody agrees with that," Trump said. "I'm sure he is a good doctor. I think he is overrated as a doctor. But we will see."

Trump also responded to Democratic frontrunner Hillary Clinton's statement that she would look forward to debating Trump.

"I probably can think of nobody I would rather debate," he said. "She was the worst secretary of state in the history of this country, although I think John Kerry is going to top her with this crazy deal he has made with Iran. … I think beating her in a debate would be one of the easy challenges of my life. That, I can say."

Fox News host Greta Van Susteren didn't accept Donald Trump's explanation that he was talking about Carly Fiorina's persona when he told a Rolling Stone writer that people wouldn't want to vote for someone with such a face.